int, float, and complex are for different purposes. async and threads paper over each others' weaknesses, instead of fixing the weaknesses at the start. Async itself is an antipattern (technical opinion, so there) but Python uses it because of the hazards and high costs of threads. Chuck Moore figured out 50 years ago to keep the async stuff out of the programmer's way, when he put multitasking into Polyforth, which ran on tiny machines. Python (and Node) still make the programmer deal with it.

If you look at Haskell, Erlang/Elixir, and Go, they all let you write performant sequential code by pushing the async into the runtime where the programmer doesn't have to see it. Python had an opportunity to do the same, but stayed with async and coroutines. What a pain.